SENSOR DEVICE

• US 20190216340A1
• Filed: 01/15/2018
• Published: 07/18/2019
• Est. Priority Date: 01/15/2018
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Inventors: HOLZ, Christian, OFEK, Eyal, SINCLAIR, Michael J.
• Granted Patent: US 10,874,305 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 2562/046 in a matrix array
• CPC Class Codes: A61B 2576/00 Medical imaging apparatus involving image processing or analysis A61B1/00009, A61B6/52 and A61B8/52 take precedence; image processing per se G06T; details of algorithms for analysing medical images G06T7/0012
• CPC Class Codes: A61B 5/0017 transmitting optical signals transmission by light H04B10/00
• CPC Class Codes: A61B 5/0024 for multiple sensor units attached to the patient, e.g. using a body or personal area network
• CPC Class Codes: A61B 5/0077 Devices for viewing the surface of the body, e.g. camera, magnifying lens
• CPC Class Codes: A61B 5/0093 Detecting, measuring or recording by applying one single type of energy and measuring its conversion into another type of energy
• CPC Class Codes: A61B 5/02007 Evaluating blood vessel condition, e.g. elasticity, compliance
• CPC Class Codes: A61B 5/02028 Determining haemodynamic parameters not otherwise provided for, e.g. cardiac contractility or left ventricular ejection fraction
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/02108 from analysis of pulse wave characteristics
• CPC Class Codes: A61B 5/02125 of pulse wave propagation time
• CPC Class Codes: A61B 5/02416 using photoplethysmograph signals, e.g. generated by infrared radiation A61B5/14552 takes precedence
• CPC Class Codes: A61B 5/02427 Details of sensor
• CPC Class Codes: A61B 5/02438 with portable devices, e.g. worn by the patient
• CPC Class Codes: A61B 5/0261 using optical means, e.g. infrared light
• CPC Class Codes: A61B 5/1075 for measuring dimensions by non-invasive methods, e.g. for determining thickness of tissue layer A61B8/0858 takes precedence
• CPC Class Codes: A61B 5/1076 for measuring dimensions inside body cavities, e.g. using catheters A61B3/1005 takes precedence
• CPC Class Codes: A61B 5/1079 using optical or photographic means
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/14552 : Details of sensors specially adapted therefor
• CPC Class Codes: A61B 5/489 : Blood vessels
• CPC Class Codes: A61B 5/6803 : Head-worn items, e.g. helmets, masks, headphones or goggles
• CPC Class Codes: A61B 5/681 : Wristwatch-type devices
• CPC Class Codes: A61B 5/6813 : Specially adapted to be attached to a specific body part A61B5/6802 takes precedence
• CPC Class Codes: A61B 5/6822 : Neck
• CPC Class Codes: A61B 5/6824 : Arm or wrist
• CPC Class Codes: A61B 5/6828 : Leg
• CPC Class Codes: A61B 5/6844 : Monitoring or controlling distance between sensor and tissue
• CPC Class Codes: A61B 5/6898 : Portable consumer electronic devices, e.g. music players, telephones, tablet computers
• CPC Class Codes: A61B 5/7207 : of noise induced by motion artifacts
• CPC Class Codes: A61B 5/7221 : Determining signal validity, reliability or quality A61B5/7207 and A61B5/7217 take precedence
• CPC Class Codes: G16H 30/40 : for processing medical images, e.g. editing

Abstract

A sensor device is described herein. The sensor device includes a multi-dimensional optical sensor and processing circuitry, wherein the multi-dimensional optical sensor generates images and the processing circuitry is configured to output data that is indicative of hemodynamics of a user based upon the images. The sensor device is non-invasive, and is able to be incorporated into wearable devices, thereby allowing for continuous output of the data that is indicative of the hemodynamics of the user.

Claims

1. A sensor device that is configured to output data that is indicative of hemodynamics of a user, the sensor device comprising:

a multi-dimensional optical sensor that is configured to be positioned proximate to a surface of skin of the user and external to a body of the user, wherein the multi-dimensional optical sensor comprises an array of photodiodes and is configured to generate images; and

processing circuitry that is in communication with the image sensor, wherein the processing circuitry is configured to;

receive the images generated by the multi-dimensional optical sensor;

validate that the images include a region that corresponds to an artery or vein of the user; and

responsive to validating that the images include the region that corresponds to the artery of the user, output data that is indicative of the hemodynamics of the user based upon the images received from the multi-dimensional optical sensor.

2. The sensor device of claim 1, wherein the multi-dimensional optical sensor is a complementary metal-oxide semiconductor (CMOS) sensor.

3. The sensor device of claim 1, further comprising:

an illuminator that is configured to emit light towards and into tissue underlying the surface of the skin of the user in a field of view of the multi-dimensional optical sensor.

4. The sensor device of claim 3, wherein the illuminator is positioned on the sensor device to be in contact with the surface of the skin of the user when emitting light towards the tissue underlying the surface of the skin of the user.

5. The sensor device of claim 1, wherein the processing circuitry, when unable to verify that an image generated by the multi-dimensional optical sensor includes a region that represents the artery or vein, discards the image such that the image is not used to output the data that is indicative of the hemodynamics of the user.

6. The sensor device of claim 1, wherein the data that is indicative of the hemodynamics of the user comprises data that is indicative of heart rate of the user.

7. The sensor device of claim 1, wherein the data that is indicative of the hemodynamics of the user comprises data that is indicative of pulse transit time or pulse wave velocity.

8. The sensor device of claim 1, wherein the data that is indicative of the hemodynamics of the user comprises data that is indicative of at least one of arterial expansion or arterial stiffness.

9. The sensor device of claim 1, wherein the data that is indicative of the hemodynamics of the user comprises data that is indicative of arterial blood oxygenation of the user.

10. The sensor device of claim 1, wherein the data that is indicative of the hemodynamics of the user comprises data that is indicative of tissue blood oxygenation of the user.

11. The sensor device of claim 1, wherein the processing circuitry is a digital signal processor (DSP).

12. The sensor device of claim 1, wherein the data that is indicative of the hetnodynamics of the user comprises at least two of the following:

data that is indicative of heart rate;

data that is indicative of pulse transit time;

data that is indicative of pulse wave velocity;

data that is indicative of arterial expansion at points along the artery;

data that is indicative of pulse pressure;

data that is indicative of a pressure wave;

data that is indicative of arterial blood oxygenation;

or

data that is indicative of tissue blood oxygenation.

13. A method for outputting data that is indicative of hemodynamics of a user, the method comprising:

with a multi-dimensional optical sensor positioned proximate to a surface of skin of a user and directed towards the surface of the skin of the user, generating a plurality of images;

based upon an image in the plurality of images, validating that the multi-dimensional optical sensor is positioned over an artery or vein of the user; and

responsive to validating that the multi-dimensional optical sensor is positioned over the artery of the user, outputting data that is indicative of hemodynamics of the user based upon the plurality of images generated by the multi-dimensional optical sensor.

14. The method of claim 13, further comprising illuminating tissue of the user in a field of view of the multi-dimensional optical sensor while the multi-dimensional optical sensor generates the plurality of images.

15. The method of claim 13, wherein validating that the multi-dimensional optical sensor is positioned over an artery of the user comprises identifying widths of the artery in the image.

16. The method of claim 13, wherein the plurality of images are captured over time, and wherein outputting data that is indicative of the hemodynamics of the user comprises:

for each image in the plurality of images, computing a mean value of pixel intensities; and

computing a pulse rate of the user based upon the mean values of the pixel intensities computed for the plurality of images.

17. The method of claim 13, wherein outputting the data that is indicative of the hemodynamics of the user comprises:

computing a value that is indicative of pulse transit time based upon the plurality of images, wherein the data that is indicative of the hemodynamics of the user comprises the value.

18. The method of claim 13, wherein outputting the data that is indicative of the hemodynamics of the user comprises:

computing values for at least two of the following group based upon the plurality of images;

heart rate;

pulse transit time;

arterial expansion;

arterial blood oxygenation;

or

tissue blood oxygenation.

19. A wearable device that is configured to be placed on a wrist of a user, the wearable device comprises:

a sensor device that is configured to output data that is indicative of hemodynamics of the user while the wearable device is positioned on the wrist of the user, wherein the sensor device is configured to compute and output values for the following;

heart rate;

pulse transit time;

arterial stiffness;

arterial blood oxygenation; and

tissue blood oxygenation.

20. The wearable device of claim 19, wherein the sensor device comprises:

a multi-dimensional optical sensor that is configured to be positioned proximate to a surface of skin of the user and external to a body of the user, wherein the multi-dimensional optical sensor comprises an array of photodiodes and is configured to generate images; and

a digital signal processor that is in communication with the multi-dimensional optical sensor, wherein the digital signal processor is configured to compute and output the values based upon the images generated by the multi-dimensional optical sensor.